Plants poison ivy

The most frequent causes of allergic contact dermatitis in the United States include plants (poison ivy, poison oak, and poison sumac), metallic salts, organic dyes, plastic resins, rubber additives, and germicides.74 The most common skin patch test allergens found to be positive in patients along with potential sources of exposure are shown in Table 32.1.75 In patients with occupational contact dermatitis who were skin patch tested, the common allergens included carba mix, thiuram mix, formaldehyde, epoxy resin, and nickel.76... 

Other chemicals may after repeated exposure cause more subtle effects on the skin such as allergic reactions. Skin sensitization can be caused by nickel in jewellery or the constituents of some washing powders. Sensitization of the skin leading to allergic, contact dermatitis can be very serious as well as disfiguring and is the most common industrial disease (see Chapter 7). Some natural toxicants, such as nettle sting (formic acid) and the very potent substances in the plant poison ivy, can be skin irritants. 

Disinfectants, insecticides, other chemicals Animal dander/products Plants (poison ivy/oak/sumac)... 

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